Tooth for excavating-shovels.



No. 783,764. PATENTED FEB. 28, 1905.

F. J. THOMAS.

TOOTH FOR EXGAVATING SHOVBLS. APPLICATION FILED OUT. 28, 1904 I Witnesses Inventor. g

Httomegs NiTnD STATES Patented February 28, 1905.

PATENT TOOTH FOR EXCAVATING-SHUt/Ehta.

SPECIFICATION forming part of Letters Patent No. 783,764, dated February 28, 1905.

Application filed October 28, 1904:. Serial No. 280,414.

To (bi/l who/rt it may concern/.-

Be it known that l, FRANK J. Tn'oMAs, a citizen of the United States, residing at ()hr1stiana, in the county of Lancaster and State of Pennsylvania, have invented a new and useful Tooth for Excavating-Shovels, of which the following is a specification.

This invention relates to excavators, dredges, and the like, and has for its principal object to provide a novel form of tooth for use at the cutting or digging edge of a bucket or scoop.

A further object of the invention is to provide a novel form of tooth having a removable point of hardened metal which will take all or practically all of the wear during the operation of the shovel and which may be readily renewed when worn away, a further bject in this connection being to provide a removable point so constructed as to resist any spreading tendency during the digging operation.

A further object of the invention is to so construct the tooth and the point that there will be no strain on the securing devices, it being possible to retain the point in place by a simple securing-bolt of small size.

With these and other objects in view, as will more fully hereinafter appear, the invention consists in certain novel features of construction and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportions, size, and minor details of the structure may be made without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawings, Figure l is a longitudinal sectional elevation of a portion of an excavating-shovel provided with a tooth constructed in accordance with the invention. Fig. 2 is a detail perspective view of the tooth properdetached. Fig. 3 is a similar view of the detachable point.

Similar numerals of reference are employed to indicate corresponding parts throughout the several ligures of the drawings.

The eXcavator-buckc .1 [so 1e usual 3pc, and to its forward or digging edge is secured a tooth of the construction best shown in Fig. 2.. This tooth is recessed to Form an upper jaw 5 and a lower jaw 6, that lit snugly against the opposite faces of the cutting edge 0! the bucket, the edgc'litting snugly and lirmly against the end wall of the recess, so that the thrust on the tooth imparted directly to the latter and not through the intervention of bolts or other securing devices. The nose of the tooth is divided by a central recess into a pair 01 tapered parallel lugs 16, that are provided with rounded points, while the end wall of the recess is arranged on a curved line, as best shown in Fig. l.

The detachable point 18 has two jaws l9 and 20, the latter being of su'liicient length to cover the whole oi the bottom ol' the lower jaw G of the tooth, and both the jaws 6 and .20 are tapered toward their rear ends in orderto reduce the extent of friction-surlace and the amount of metal used. The wall at the juncture of the two jaws l9 and 20 is rounded to Follow the contour of the rounded ends of the lugs 16, and the parts are arranged to lit very closely together, so that the point will not become jammed nor will there be any strain on the securing means.

In removable points ol the generalclass to which the invention relates, especiz'tlly where the points are bifurcated to form a pair of jaws, it is found that during the operation of the shovel there is a constantstrain on said jaws in opposite directions, and the tendency oi" said jaws to spread while at work throws considerable strain on the securing devices, the latter becoming worn or broken after being used for a short time. in the present case this is prevented by a connecting web or rib 21, that firmly unites the two jaws to each other, and the rear edge of said web or rib is arranged on a curved line following the contour of the inner wall of the recess 15, so that the end wall of said recess will lit snugly against the end of the rib and the working strain will be transmitted directly from the tooth to the point, and the web, in addition to preventing any spreading movement ol the jaws, serves further to prevent any tendency to lateral displacement, the tooth and point being locked transversely.

The points are preferably made of steel cas tings and are made in quantities, anumber'being supplied to each shovel, but as the points are not renewed very frequently the reserve supply will become oxidized to some extent and dirt will accumulate in the space between the two jaws. rendering it diflicult to secure perfect fitting of a new point on the nose of the tooth. To overcome this difficulty, the inner end of the web 21 is recessed, so that a clean passage is formed from side to side of the point at the line of juncture of the two jaws and any accumulations of dirt or rust may be readily removed.

With a tooth constructed in accordance with this invention all of the wear will be directly on the detachable point, the under surface of the jaw 20 of the latter protecting the whole of the lower face of the jaw 6 of the tooth, and as the parts are fitted snugly the strain transmitted from the shovel through the tooth and from the latter to the point is through parts that are in direct contact with each other, so that there is no tendency to shear the securingbolts. Inasmuch as the parts are interlocked transversely, there is'no lateral strain on the bolts, and it is found that a single securingbolt of comparatively small diameter is all that is necessary to hold the parts together. The securing bolts or bolt are arranged in countersunk openings in the jaw 20 of the point, and in the upper portion of the tooth are arranged recesses for the reception of nuts of said bolts.

The detachable points are formed of caststeel and the formation of the recess or opening in the web permits the cleaning out of the castings and insures the perfect fitting of the point. In these devices as usually constructed it is impossible to clean out or dress the-casting if the latter are made of steel except at prohibited cost, but in the present case the dressing may be readily accomplished and perfect fit insured.

Having thus described the invention, what is claimed is- 1. In a tooth for excavating-shovels and the like, a-body portion comprising a pair of jaws for engaging the opposite faces of the shovel, and forwardly extended in the form of a pair of spaced lugs,-and a detachable point having a web fitting between said lugs.

2. A tooth having a forwardly-projecting nose divided by a recess into two lugs, and a detachable point bifurcated to form a pair of jaws that embrace the two lugs, said jaws being united by a web that fits within the recess.

3. A tooth having a body portion recessed to form a pair of jaws that embrace the edge of the shovel, and a detachable point bifurcated to form a pair of jaws that embrace the nose of the tooth, the lower jaw being extended rearward to protect the whole of the lower surface of the lower jaw of said body portion.

A. A tooth having a forwardly-extended nose formed of a pair of tapered lugs disposed in spaced relation, the inner wall of the nose between said lugs being arranged on a curved line, and a detachable point having a pair of jaws embracing the nose, said jaws being rigidly connected by a web that is provided with a curved face fitting against the curved wall of the recess.

5. The combination with a tooth having a forwardly-extended nose that is provided with a recess, and a detachable point interlocking with the nose, said point being bifurcated to embrace the nose portion and having a central web fitting snugly within said recess.

6. The combination with a body portion bifurcated to form a pair of jaws for engaging the two surfaces of the shovel-blade, the forward end of the body portion being extended to form a nose that is divided by a central recess into two lugs, and a detachable point having a pair of jawsembracing the nose, the two jaws being connected by a web that extends from the rear edge of the upper jaw to a point intermediate of the length of the lower jaw.

7. The combination with a tooth having a body portion recessed for the reception of the shovel-blade, the forward end of said body portion being further extended to form a nose that is divided by an intermediate recess into a pair of lugs, and a detachable point having jaws embracing said lugs, the two jaws being connected by a vertical web, and the base portion of said web being provided with an opening to facilitate the removal of foreign matter between the jaws.

8. A shovel-tooth having a projecting recessed nose, and a detachable point having a web fitting within said recess.

9. A shovel-tooth having a projecting recessed end, and a detachable point provided with a web fitting within-said recess, the base of the web having an opening to permit cleaning of the point.

10. A detachable point of the class specified, comprising an approximately wedge-shaped piece of metal, bifurcated to form a pair of jaws, and an integral web for uniting the jaws to each other, said web having an opening for the passage of a cleaning-tool.

In testimony that I claim the foregoing as my own I have hereto afiixed my signature in the presence of two witnesses.

FRANK J. THOMAS.

\Vitnesses:

WILLIAM SEVERIN, JOHN H. WHEELER. 

